Creating new perks?

[Burut]

Under perks I mean the unit specific buffs that are written in their unit card. Example for that is Knight's "Valor" (+1 morale), or Robbers "Robber" (-1 morale to all 1-2 level Humans). Was wondering if you can copy them, rename them, change the text when you hover over them, and play with creating new effects, for example if I wanted to create a "Vagrant" perk (+2 morale if no Humans in your army). Is there any way to do this?